A rotor is deployed such that the rotor becomes coaxially rotatable with a stator. Opposite sides of the adapter body are configured to respectively engage a camera and a lens. A nozzle needle which has an adjustable stroke is disposed in the needle section for controlling an injection of fuel through the at least one injection hole. 2 dBkm or less at a wavelength of 1550 nm, wherein the relative refractive index difference 1 between the center core portion and the clad portion is 0. The drain assembly is configured to receive moisture from the flexible sheet.